Method for manufacturing semiconductor device

Abstract

There are prepared a semiconductor substrate having a first main surface and a second main surface, and an adhesive tape having a third main surface and a fourth main surface, the first main surface having a maximum diameter of not less than 100 mm. The semiconductor substrate fixed to the third main surface of the adhesive tape is placed in an accommodation chamber. The accommodation chamber is evacuated while maintaining a temperature of the adhesive tape at not less than 100° C. An electrode is formed on the second main surface after the step of reducing the temperature of the semiconductor substrate. The step of evacuating the accommodation chamber includes a step of evacuating the accommodation chamber while maintaining the temperature of the adhesive tape at not less than 100° C. with a space being provided between the fourth main surface of the adhesive tape and the substrate holding unit.

The invention claimed is: 
     
       1. A method for manufacturing a semiconductor device comprising steps of:
 preparing a semiconductor substrate, an adhesive tape, and a substrate holding unit, the semiconductor substrate having a first main surface and a second main surface opposite to the first main surface, the first main surface having a maximum diameter of not less than 100 mm, the adhesive tape having a third main surface and a fourth main surface opposite to the third main surface, the substrate holding unit being provided to be capable of holding the semiconductor substrate; 
 fixing the first main surface of the semiconductor substrate to the third main surface of the adhesive tape; 
 placing, in an accommodation chamber, the semiconductor substrate fixed to the third main surface of the adhesive tape; 
 evacuating the accommodation chamber while maintaining a temperature of the adhesive tape at not less than 100° C.; 
 reducing a temperature of the semiconductor substrate after the step of evacuating the accommodation chamber; and 
 forming an electrode on the second main surface of the semiconductor substrate after the step of reducing the temperature of the semiconductor substrate, 
 the step of evacuating the accommodation chamber including a step of evacuating the accommodation chamber while maintaining the temperature of the adhesive tape at not less than 100° C. with a space being provided between the fourth main surface of the adhesive tape and the substrate holding unit. 
 
     
     
       2. The method for manufacturing the semiconductor device according to  claim 1 , wherein
 the step of evacuating the accommodation chamber includes a step of evacuating the accommodation chamber while maintaining the temperature of the adhesive tape at not less than 100° C. with the fourth main surface of the adhesive tape being in contact with the substrate holding unit, after the step of evacuating the accommodation chamber while maintaining the temperature of the adhesive tape at not less than 100° C. with the space being provided between the fourth main surface of the adhesive tape and the substrate holding unit. 
 
     
     
       3. The method for manufacturing the semiconductor device according to  claim 1 , wherein
 the substrate holding unit includes a heater provided to be capable of heating each of the semiconductor substrate and the adhesive tape, and 
 the space is maintained at not less than 0.5 mm and not more than 2.0 mm in the step of evacuating the accommodation chamber while maintaining the temperature of the adhesive tape at not less than 100° C. with the space being provided between the fourth main surface of the adhesive tape and the substrate holding unit. 
 
     
     
       4. The method for manufacturing the semiconductor device according to  claim 1 , further comprising a step of grinding the second main surface of the semiconductor substrate after the step of fixing the first main surface of the semiconductor substrate to the third main surface of the adhesive tape and before the step of evacuating the accommodation chamber while maintaining the temperature of the adhesive tape at not less than 100° C. 
     
     
       5. The method for manufacturing the semiconductor device according to  claim 4 , wherein in the step of grinding the second main surface of the semiconductor substrate, the semiconductor substrate is ground until the semiconductor substrate has a thickness of not more than 200 μm. 
     
     
       6. The method for manufacturing the semiconductor device according to  claim 1 , wherein in the step of evacuating the accommodation chamber, H 2 O partial pressure in the accommodation chamber is reduced to not more than 5×10 −4  Pa. 
     
     
       7. The method for manufacturing the semiconductor device according to  claim 1 , wherein in the step of evacuating the accommodation chamber, the temperature of the adhesive tape is maintained at not less than 120° C. and not more than 200° C. 
     
     
       8. The method for manufacturing the semiconductor device according to  claim 1 , wherein the semiconductor substrate includes silicon carbide. 
     
     
       9. The method for manufacturing the semiconductor device according to  claim 1 , wherein the step of forming the electrode includes steps of:
 forming a metal layer on the semiconductor substrate; and annealing the metal layer. 
 
     
     
       10. The method for manufacturing the semiconductor device according to  claim 9 , wherein in the step of forming the metal layer, H 2 O partial pressure in the accommodation chamber is reduced to not more than 1×10 −4  Pa. 
     
     
       11. The method for manufacturing the semiconductor device according to  claim 9 , wherein the step of forming the metal layer is performed by a sputtering method. 
     
     
       12. The method for manufacturing the semiconductor device according to  claim 9 , wherein in the step of forming the metal layer, the metal layer is formed while cooling the semiconductor substrate. 
     
     
       13. The method for manufacturing the semiconductor device according to  claim 9 , wherein the step of forming the metal layer includes steps of: conveying the semiconductor substrate to a film formation chamber provided to be coupled to the accommodation chamber; and forming the metal layer on the semiconductor substrate in the film formation chamber. 
     
     
       14. The method for manufacturing the semiconductor device according to  claim 9 , wherein in the step of forming the metal layer, the metal layer is formed to have an in-plane film thickness distribution of less than 6%.